This thesis explores issues in the development of foreign language writing abilities in a Portuguese setting. The study is based on a research project carried out in 1993 in three University classrooms, where the author was teaching. It investigates what happens when educational drama is brought into the EFL classroom as part of a teaching programme with a view to improving writing abilities. Set in a Vygotskian framework, educational drama is used as a mediating device to attend to a whole set of factors not usually salient in L2 writing. The study covers all 108 students majoring in EFL at that time. The students were proficient in both oral work and grammar exercises but had difficulties writing in English. Two obligatory drama workshops were carried out in English with each group of students during their second term of study and all written work carried out during the term stemmed from the workshops. Large amounts of data were analysed by qualitative and quantitative methods. Writing assignments pre/post drama workshops were collected. Drama workshops were monitored via audio and video recording. Questionnaires were given to the students during the pre and post data collection periods to measure writing apprehension. Student writing was found to improve significantly in both content and grammatical fluency in a relatively short period of time. Drawing on linguistic and social semiotic analyses, the project examines the nature of the different written texts produced in this particular educational environment and the interaction between the use of drama and the writing process itself through the concept of transformation. In terms of a larger Vygotskian framework it looks at the role of thinking in learning, development and instruction in a way which bridges difficult conceptual phases in foreign language teaching. Key words: EFL, foreign languages, writing, Vygotsky, drama, Social Semiotics, transformation.